New supported media types for the `Catalyst Signed Document`

[Mr-Leshiy]

Summary

Modify the existing ContentType rule to support a freshly added new variants in the spec

Description

; Supported Content Media Types.
; If the Media Type is supported by COAP, then the `uint` CoAP encoded
; version of the media type must be used, in preference to the string.
media_type = (
    (uint .eq (0 / 50 / 60 / 20000)) /
    (tstr .eq (
        "application/cbor" /
        "application/cddl" /
        "application/json" /
        "application/schema+json" /
        "text/css; charset=utf-8" /
        "text/css; charset=utf-8; template=handlebars" /
        "text/html; charset=utf-8" /
        "text/html; charset=utf-8; template=handlebars" /
        "text/markdown; charset=utf-8" /
        "text/markdown; charset=utf-8; template=handlebars" /
        "text/plain; charset=utf-8" /
        "text/plain; charset=utf-8; template=handlebars"
    ))
)